The Nor Block (Not Or) - Mitsubishi Electric a2 Series Programming Manual

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2 Simple Application Controllers
5.6

The NOR Block (Not OR)

The Output comes ON when all the inputs are OFF.
The Output remains OFF if any input is ON.
If no Input pin is used, the block output is OFF.
Unused Inputs are considered to be OFF
This block is equivalent to an OR block followed by a NOT block
Table: 5.7: NOR Logic gate
Input 1
Off
On
On
On
On
Off
On
On
On
Off
Off
Off
On
Off
Off
Off
01
1
Output
2
3
4 NOR
Input 2 Input 3
Off Off
On On
On On
On Off
Off On
On On
On Off
Off On
Off Off
On On
On Off
Off On
Off Off
On Off
Off On
Off Off
Input 4 Output
Off On
On Off
Off Off
On Off
On Off
On Off
Off Off
Off Off
On Off
Off Off
On Off
On Off
Off Off
Off Off
Off Off
On Off
The Logic Function Blocks 5
1 0 0
O
2
3
N O R
4
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